Four Penn State faculty experts are scheduled to appear tonight and next Friday (April 18 and April 25) on the ABC television news program "20/20" in two shows partly devoted to wild weather and weather myths. Sam Champion, weather anchor of ABC's "Good Morning America" and weather editor of ABC News, traveled to Penn State in late March to interview the faculty members.

In Key West, Florida, tourists flock to Mallory Square at the end of the day to watch the sun set. Street performers entertain waiting crowds with magic and vendors sell souvenirs of the daily sunset celebration. Flashes click as tourists try to capture the beautiful orange sun as it disappears behind the sparkling blue ocean.

In almost every location around the globe, the sky appears orange at sunrise and sunset. What causes this colorful phenomenon?